Leveling-instrument



(No Model.) 7

- L. 0. STRONG.

LBVELING INSTRUMENT.

No. 297,093. w Patented Agr. 15., 1884.

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LEVELING-INSTRUMENT.

SPECIFICATIQN forming part of Letters Patent No. 297,093, dated April15, 1884-.

Application filed October 3, 1883. (No model.)

To aZZ whom it 1mm concern.-

Be it known that I, LEVI O. STRONG, of the city and county of Albany, inthe State of New York, have invented certain new and useful Improvementsin Leveling-Instrume11ts, of which the following is a specification.

My invention consistsin combining,with an ordinary spirit-level, certainappliances and instrumentalities, herein described, whereby the saidlevelis adapted to be optionally used, in addition to the uses to whichit is commonly applied, for the following purposes: as a surveyorslevel, a plumb, an implement for determining angles on horizontal andvertical planes.

The object of my invention is to provide an inexpensive and reliableimplement that can be readily applied to the uses above set forth. Iattain this object by means of the construction illustrated in theaccompanying drawings, which form part of this specification, and inwhich' Figure 1 is a side elevation of my levelinginstrumentarranged asa snrveyors level, with parts of the supporting-stand shown in verticalsection; Fig. 2, an enlarged vertical sec tion of the frame-work andspirit-level on the line 00 of Fig.1; Fig. 3,2111 end elevation of thetelescope end of the spirit-level frame detached from itssupporting-stand; Fig. 4:, a like View of the opposite end of thespirit-level frame; Fig. 5, a plan view of the graduated table of thesupporting-stand; Fig. 6, a plan View of the top plate for thesupporting-stand. Figs. 7 and 8 are respectively a plan view and endelevation of the clamppiece and center-pin, whereby the spirit-level isattached to the supporting-stand; Fig. 9, a rear elevation of thecentral part of the spirit-level frame-work, and Fig. 10, alongitudinalsection of the telescope sight.

As shown in the drawings, A is the framework for the spirit-level,having its upper and lower edges made in perfect parallelism with eachother, and which is preferably made in the form of an open-work metallicframe having a central circular flange, a, provided with a central seat,a, which is connected to the eircular flange by means of radial arms a",one of said arms being preferably made parallel with the upper and loweredges of the frame-work I A, and the other arms perpendicularly there-The carrier 13 for the spirit-level tube 0 is pivoted to the seat a bymeans of the centerpin, I). Said carrier is provided with two arms, I),having U-shaped terminals for re ceiving the spirit-level tube 0, eachof said arms being also provided with an adjustingscrew, If, forregulating spirit level in a true position in respect to the edges ofthe framework A. A binding-screw, b, which passes through a segmentalslot, 1)", in the ca-rrierB, permits the latter to turn on itscenter-pin, I), so as to set the spirit-level in a horizontal positionand determine the angular position of the frame-work A at any time. Anadj ustable pointer, [2 is pivoted to the lower part of the carrier B,and is secured thereto by binding-screws I). The said pointer, when thespirit-level has been properly adjusted, should be arranged to coincidewith the zero-point on a graduated quadrant, D, fixed inside of thecircular flange a, and when so adjusted, the angle at which theframework A may at any time be placed can be readily ascertained byfirst turning the spirit-level tube 0 into atrue horizontal position,and then noting the point on the quadrant D at which the pointer b isstanding. The quadrant D should be graduated to correspond to thedegrees of a circle, and, in addition, may be graduated to any requiredfractions of such degrees. The said quadrant should be secured withinthe circular flange a, as shown in Fig. 1.

At one end of the frame-work A atelescopesight, E, is arranged, the saidsight being preferably connected to said frame-work by means of aswinging joint. The sight E consists of a cylindrical tube that isprovided at one end with a cap, a, which contains a small centralaperture. The swinging joint consists of a link, 0, that is pivoted atone end to the sight E, and at the opposite end to the frame work A, andit is so arranged that the sight E may be thrown up to lie on the upperedge of the framework A, as shown by the full lines in Fig. 1., or beturned down into a recess in the end of the frame-work, as indicated bythe dotted lines in the same figure. A spring, 0", fixed in the end ofthe link a, attached to the sight E, exerts its pressure beneath theouter end of said sight in such man- I cure the spirit-level in place.

ner that it (the sight) will be maintained in its required place ineither position above described. The link a at its end that is pivotedto the framework A is provided with a head, 6 which bears against aspring, a, (that is fixed in the framework A,) so as to retain the sightE securely in place in both positions above described. At the oppositeend of the frame-work A a pointed sight, F, is pivot ed in such mannerthat it may stand erect, as shown by the full lines in Fig. 1, or beturned down into a recess in the framework, as indicated by the dottedlines in that part of the same figure; and in either position the saidpointed sight is securely held in place by means of a spring, a", thatis fixed in the frame work A for that purpose, the said spring beingarranged to exert its pressure against the head f, formed on said sight.The sights E and E must be adjusted to range in exact line with thebottom edge of the frame-work A, and when constructed and adjusted asabove described, my level, when detached from the sup11 orting-stand,hereinafter described, may be used in any manner that an ordinaryspiritlevel can, and it can also be employed for the followingadditionalpurposes: for determining verticals and angles, and by usingthe sights E and F for obtaining correct ranges for distant anddisconnected parts, either 011 horizontal or inclined planes.

The supporting stand for my improved spirit-level is constructed of thefollowing parts: A top plate, G, is provided with lugs g, to which thelegs 9 of the tripod are pivoted. Said top plate has in its center acircular opening, 9*, for receiving an inverted cup, which forms, inconjunction with said opening, a universal joint. A circular graduatedtable, II, is provided with a central socket, h, which screws into theinverted cup ii, that fits into the opening of the top plate, G. Thetable II is supported 011 four adjusting screws, 7f, whereby said tablecan be brought into a perfectly-level position. The upper face of saidtable is marked with graduations of the degrees of a circle or anyrequired fractions thereof. The said table is also provided with pins orstuds it, that are fixed in its surface, and arranged in such mannerthat an arm or index attached to the center-pin of the spirit-level canbe moved ninety degrees between said pins.

The center-pin I has on its upper end abottom plate, t, which,with itsside flanges, t", form a channel for receiving the bottom edge of theframe-work A. A clamping-screw, 2', inserted in one of the flanges z",bears against the bottom flange of the framework A, so as to se Thecenter-pin has its lower part accurately fitted into the socket 71, butis left free to turn therein.

An arm or index, J, is arranged to be attached to the center-pin I, andfor that purpose is provided with a binding-screw, j. The said arm, whenthe screw 3' is slackened, permits the center-pin I to turn freelytherein, in order that the sightsEand F may bebrought to range truly onany required line, and,when that range has been obtained, the arm J canbe secured in position in juxtaposition with any point on the graduatedcircle on the table II. Then by taking that point as a datum line, theangularity of any other line on a horizontal plane may be obtained byturning the framework A (and its attached center-pin I and arm J untilthe sights E and Frange accurately on the new line, and taking thedifi'erence between the first and final positions of the arm J, asrepresented by the graduations on the table II.

I claim as my invention 1. The combination, with the frame A for aspirit-level, having a central seat, a, as herein set forth, and thegraduated quadrant D, of the carrier 13, pivoted to the seat a, andprovided with arms I) for containing the spiritlevel tube 0, the saidcarrier having the adjusting-screws If, binding-screw b, and ad justable pointer Z)", all constructed and arranged to operate as hereinspecified.

2. The combination, with a spirit level frame, A, having the sights Eand F attached thereto, substantially as set forth, of a centerpin, I,provided with flanges z" and clampingscrew i whereby the saidspirit-level frame is attached to and adapted to revolve in asupporting-stand, as and for the purpose herein I specified.

3. In a supportingstand for a spirit-level frame, A, provided withsights E and F, as herein set forth, the combination, with the graduatedtable II, )rovided with a central socket, h, and supported onadjustingscrews if, as herein described, of the center-pinI and arm I,the latter being adj ustably connected to said centerpin, as and for thepurpose here in specified.

4E. The combination, with the graduated table II, provided with thestuds or pins h, of the center-pin I, having a movable arm or index, J,attachable thereto, for the purpose of limiting the rotatory movement ofthe center-pin I to the part of the circle intervening between the pinsIf, as and for the purpose herein specified.

LEVI G. STRONG.

Witnesses:

7M. H. Low, H. V. Solurrnncooi).

IOO

